Had a couple of problems making KDE4 load on my desktop. At first I though the packages were wrong but after thinking for a second, why would rworkman release something that isn’t working? I doubt that the packages were wrong so I’ve started poking around and check the logs. KWin was the culprit so I though maybe that there was something that wasn’t initialising like it should.
I’ve also added /etc/profile/qt4.sh and qt4.csh to make sure it loads qt4. It’s basically a copy of qt.sh but with the number 4. 
Check this thread for more information about this.
Apparently, NVIDIA cards on KDE4 is an issue according to various thread on the net so to test it up, I changed the driver in my xorg.conf from nvidia to nv and voila it worked. Something was wrong with my nvidia driver. I poke some more and found a couple of other thread about this issue. Here is what I added to my xorg.conf file.
Section "Device"
Driver "nvidia"
Option "NoLogo" "1"
Option "RenderAccel" "1"
Option "AllowGLXWithComposite" "1"
Option "AddARGBGLXVisuals" "1"
EndSection
I also had to rebuild my nvidia driver for some reason the GLX wouldn’t load. After that I’ve rebuilt against the kernel I am running, it worked flawlessly. Cool!